Boiler feed automatic control



s. c. H'ULETT 2,011,637

"BOILER FEED AUTOMATIC CONTROL Filed Apri l 1952 gmmlom Schuyler C Hu/eiz r PATENT orrics 2,011,637 H Boater t FEED AUTOMATIC GONTROL Schuyler C'. Hulett; Spokane, Wash. Applicatiori A-pfil 25 1932; Serial- No; 607,276" I mains. (013-200- 152 ivrypres nt invention relates to boiler reed automatic controls andflis an improvement over'the device" disclosed in myfcwpending patent application entitled Automatic boiler feed controls,

Serial Number 585,941 and filed January 11, 1932.

The primary objects of my present invention are to improve and simplify the device embodied in my prior application by eliminating the pivotally mounted float and associated elements and substituting therefor a plurality of stationary contact tubes, preferably filled with iron clippings,

and whereby the water is used as a direct agent in carrying the current through the device at different levels to cause its functioning in automatically maintaining water supply within a boiler.

The above and other objects are accomplished by the devices shown in the accompanying drawing; wherein: Figure l is a general view in'elevation showing a portion of a boiler with my device installed thereon and also showing a wiring diagram; Fig. 2 is a view in elevation of the control casing with its cover removed and showing certain parts broken away; Fig. 3 is an enlarged view in transverse vertical section through Figs 2; and Fig. 4 is an enlarged'detail view in vertical section showing the lowermost one of the metal contact tubes and associated parts.

Referring to the drawing, the numeral 5 designates a boiler which is supplied with water by a motored pump 6 through a pipe '7. A water glass 8 is connected to said boiler in the usual manner and upperand lower pipes 9 and I0 respectively connect said waterfglass with the top and bottom of a control casing II which is disposed in parallelrelation with the water glass whereby the water level within the boiler is maintained within the glass and casing as will be understood.

The control casing I! is provided with a plurality of metal contact tubes as designated by the numerals i2, i3, and I l. Said tubes are mounted in horizontal spaced apart relation, one above the other, in'a frame l5 within the casing and insulated from the frameby porcelain bushings IS on the ends of the tubes as most clearly shown in Fig. 4. Said tubes are preferably filled with iron clippings or'filings, as shown at ii, and are provided with a plurality of holes l8 so that the water'within the casing has ready access to the I surface area of contact by the water thus ensur ing and making a better contact.

Referring to Figs. 1 and 2, the contact tube (2 i's'c'o'nriectcl at feta-2'. p ng menswear: ea ng tog soierlqid cg 22; the tube 13f s cpri nested at 23- t'c a plug 24' having" wire it wading 21 to a plug 28 having a wire 29 leading to a solenoid 3|]. Said plugs are somewhat similar to a spark plug and are threadedly connected to the casing H and are mounted within a sub-casing 3| that is connected to the main casing. The solenoid coils are mounted on a switchboard 32 m and are similar to those described in my abovenamed co-pending patent application so that no description in detail of same isbelieved necessary herein. The pivoted switches 33 of the solenoids are of the mercury contact type and are normally closed by a counterweight 34 and the passage of current through the coils of said solenoids causes said switches to open thus shutting off the current. As set forth in the aforesaid co-pending application the lower ends of the switches are 20 immersed in mercury when they are closed by electrical energy and the counterweights normally retain said switches raised and out of contact with the mercury.

Referring now to Fig. 3 of the drawing, the normal level of the water within the boiler is coincident with a point between the contact tubes I2 and 33 within the casing H and the tubes l3 and M are therefore submerged. Said casing being, grounded on the boiler, current, will flow through the solenoids 26 and 30 from the outside source over the wire 35 and its connections thus holding the mercury switches of said solenoids open; Now should the water level drop below the tube I3 no current will flow through the solenoid 26 and the counterweight will close the switch of said solenoid causing the current to flow through a resistance 36 and toa solenoid 3'! which will close its mercury switch, as in my former application, whereby current will flow 40 through the motor of the pump 6 and cause said pump to raise the water level within the boiler.

When the water level within the boiler 5 reaches a height whereby the contact tube I2 is submerged current will flow through the solenoid 22 thus opening its switch and cutting olf the current supply tothe motor of the pumpfi. If for any reason the water level should drop below the contact tube M the current to the solenoid 30 will be disrupted and theswitch of said solenoid will be closed by its counterweight 34 thus throwing the current through a transformer 38 to a bell 39 and sounding the alarm, or if theboiler is fired by a stoker the current will or may be made to shut. oif the stoker motor as in my prior patent application.

' ;'qri fitidn at thejtopjiand bottornof tha :ing a metal framemounted within the casing,' a

tr-Q m a sw m tu e h r n and.

metalconductorpipe 50 extends from the subcasing 31 to the switchboard 32 and houses'the three wires 2i, 25, and 29, t

While the foregoing brief description is made in order to convey a general idea of the application and operation of mypresent invention; it

will beunderstood that the novelty of this in-t ventio'n resides essentially in the contact tubes and their connections; Said tubes eliminate the necessity of 'using a pivotally mounted float, as

used my prion-patent application; and-thus simplify "the device by doing awaywiththis movable element.

l-lavingfthus described my invention, it being understood that such changes'in its construction and arrangement may be resorted to as do not constitute a departure from the :scope and spirit" of theinvention, What I claim cure by Letters Patent is:

1. Ina boiler feed automatic control, a'switch mechanism comprising a main metal casing, pipe and desire to se 1 of the sub casing.

insulatively supported by the frame, a plurality of plugs threadedly connected through a side of the casing inassociated relation with the contact tubes, a wire connecting each of said plugs with its associated tube, and a'wire connected to and leading from each of said plugs.

2. In a, boiler feed automatic control, a switch mechanism comprising a main metal casing, pipe connections at the top and bottom-of the easing; ametal frame mounted within the casing, a plurality of metal contact tubes horizontally and 'ins'ulatively' supported by the frame, each of said tubes having a series of holes in its upper surface, a filling of iron filings for each of said tubes, a sub-casing connectedrto one side of the main casing, a plurality of plugs threadedly con-' nected through the side ofthe main casing in associated relation with the contact tubes and projecting into the sub-casing, a Wire connecting each of said plugs with its associated tuba and .a wireflleadi g frome each or said plugs ei rteriorly 

